brew install android-sdk # will install the newest SDK starter package
android update sdk # this will open the UI, now install all platforms
chgrp -R staff /usr/local/Cellar/android-sdk/r7 # otherwise the ANDROID_HOME will be owned by the wheel group and you may not start anything as non admin user.

To use tools like the emulator add ANDROID_HOME and ANDROID_SDK_ROOT to your $HOME/.profile or $HOME/.bash_profile (if the latter exists, use this):

Create an emulator called Wildfire using the android command. Now if you want the emulator to be started automatically after you login, put the following into $HOME/Library/LaunchAgents/emulator-wildfire.plist:

After you saved the file, execute launchctl load $HOME/Library/LaunchAgents/emulator-wildfire.plist. From now on the emulator starts whenever you (or your CI user) logs in.